1. Field of the Invention
This invention relates to an apparatus and method for sensing undesired flammable vapors at or near gaseous fuel-fired burners such as may be used for gas-fired appliances, for example residential gas-fired water heaters.
2. Description of Prior Art
Safety issues are important considerations in the design, manufacture and operation of gaseous fuel-fired burners, such as found in gas-fired appliances. This is especially true for appliances operated in a residential environment. Such appliances include residential gas-fired water heaters, gas-fired clothes dryers, furnaces, etc.
One safety issue involves a potential danger which arises when burners are exposed to flammable vapors in the ambient atmosphere external to the appliance. Such flammable vapors can cause uncontrolled propagation of flames and/or possible explosions.
An object of this invention is to provide a burner for a gas-fired appliance, capable of detecting and responding to the presence of undesired flammable vapors at, near or in the vicinity of the burner. One goal would be to turn down and/or completely shut off a gaseous fuel supply to the burner, to prevent an undesired propagation of flame and/or an explosion.
Another object of this invention is to provide a flammable vapor sensing burner which has a high degree of sensitivity to respond to even very low concentrations of detected flammable vapor.
Still another object of this invention is to provide a burner having a simplified construction with low cost, long life expectancy and enhanced durability of construction and reliability of operation.
These and other objects of this invention will become apparent in light of the present specification, the claims and the drawings.